Niagara Falls [ a ] is a group of three waterfalls at the southern end of Niagara Gorge , spanning the border between the province of Ontario in Canada and the state of New York in the United States. The largest of the three is Horseshoe Falls , which straddles the international border of the two countries. It is also known as the Canadian Falls.
Lawrence River , the combined falls have the highest flow rate of any waterfall in North America that has a vertical drop of more than 50 m ft. During peak daytime tourist hours, more than , m 3 5. Balancing recreational, commercial, and industrial uses has been a challenge for the stewards of the falls since the 19th century.
Niagara Falls was formed when glaciers receded at the end of the Wisconsin glaciation the last ice age , and water from the newly formed Great Lakes carved a path over and through the Niagara Escarpment en route to the Atlantic Ocean. Horseshoe Falls is about 57 m ft high, [ 4 ] while the height of the American Falls varies between 21 and 30 m 69 and 98 ft because of the presence of giant boulders at its base.
The larger Horseshoe Falls is about m 2, ft wide, while the American Falls is m 1, ft wide. The distance between the American extremity of Niagara Falls and the Canadian extremity is 1, m 3, ft.
This is accomplished by employing a weir — the International Control Dam — with movable gates upstream from Horseshoe Falls. Water diversion is regulated by the Niagara Treaty and is administered by the International Niagara Board of Control.
